<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>盒子模型之边框</title>
    <style>
        div {
            width: 200px;
            height: 200px;

            /* border-width: 5px; */

            /*  solid：实线边框  dashed：虚线边框  dotted：点线边框*/
            /* border-style: solid; */
            /* border-style: dashed; */
            /* border-style: dotted; */

            /* border-color: pink; */

            /* 边框的简写 */
            /* border: 1px solid pink; */
            /* border-top: 5px solid red; */
            /* border-left: 1px dashed pink; */
            /* border-bottom: 2px dotted blue; */
            /* border-right: 3px solid green; */


            /* 要求：200*200盒子 上边框为红色 其余的为蓝色 */
            /* 层叠性 只层叠了上边框 */
            border: 5px solid blue;
            border-top-color: red;

        }
    </style>
</head>

<body>
    <div></div>
</body>

</html>